An improved handle for a steerable catheter apparatus steerably manipulated by steering wires or rods, and including an elongated housing having one end thereof adapted for attachment to the proximal end of the steerable catheter； a steering actuator carried by the housing and including an elongated lever pivotally affixed to the housing and rotatable about an axis transverse to both the length of the housing and the length of the lever and further having an end thereof attached to the steering wires or rods of the catheter to cause deformation of at least a portion of the catheter； and a locking mechanism carried by the lever for selectively locking the steering actuator in place relative to the housing during at least a portion of the time of use of the catheter apparatus.
